Anti-gravity circuit
From Jenny Everywhere Wiki
An anti-gravity circuit, also known as an anti-grav engine, was a device which could be tacked onto a machine and enabled it to fly, free of gravity. Clockwork Cherubs of the Crew of the Copper-Colored Cupids needed to have anti-gravity circuits, and to have them switched on, to be able to fly. This was not universal; for example, Juliet-178 was actually officially banned by the Cupid Parliament from using an anti-grav engine, although she owned one anyway. (PROSE: The Time of the Toymaker)
